Current Transformers

Telcon is a world leader in the field of soft magnetic cores and components, GD Rectifiers are an official distributor for their Current Transformers.

The Telcon HES range of panel mounted units cover the range from 25A - 500A and consist of the coil and Hall element only where the user includes the active circuitry on their PCB. All units are designed for primary current cable and are available for vertical mounting (up to 100A) and horizontal mounting (25A - 500A).

Telcon's DCVT range of self powered units provide an isolated DC voltage output for a DC voltage input. The DCVT5U, DCVT5S and DCVT8HV have basic 25V:10V ratio, expandable by the insertion of resistance in series with the input. The DCVT5x types are proof stress tested to 6kV and the DCVT8HV to 10kV.

Sirio is a leading manufacturer of electromagnetic components for applications in industrial electronics.

GD Rectifiers are the UK's leading distributor for Sirio components, who specialise in the development and production of three types of current transformers:

Main Frequency Current Transformers

Main frequency current transformers are used to measure alternate currents at 50-60 Hz, up to 600 Arms.

They are based on toroidal Silicon Iron core; they typically have a high number of secondary turns, so that the secondary current is relatively low. By connecting a burden resistance to the secondary side, you can read a proportional voltage signal, isolated from the mains. As the secondary current is low, the low power burden resistance can be connected to the PCB.

Current Transformers for Measurement Applications

Current transformers for measurement purposes are used to measure alternate currents at 50-60 Hz, up to 50 Arms. They are typically used in energy metering applications, where high accuracy and small dimensions are required at the same time.

Current transformers for measurement applications are available in two different versions; with passing-through hole and with the primary turn inside, this was developed to get an easier assembly process on the PCB.

Current Transformers for High Frequency Applications

Current transformers for high frequency applications are used to detect high frequency currents, in order to protect an electronic switch against overcurrents in switching converters. They are typically connected at the primary side of medium-high power high frequency transformers, but they are also suitable for currents measurement, in applications which do not require high accuracy, but prompt response of the measurement equipment instead.

They are developed to detect alternate currents in the frequency range of some kHz. By connecting a burden resistance to the secondary side, you can read a proportional voltage signal, isolated from the mains. Depending on the application, other types of signal processing are available to use either by using digital or analogue techniques.